CA1170682A - Wrap element and tip seal for use in fluid apparatus of the scroll type and method for making same - Google Patents
Wrap element and tip seal for use in fluid apparatus of the scroll type and method for making sameInfo
- Publication number
- CA1170682A CA1170682A CA000389369A CA389369A CA1170682A CA 1170682 A CA1170682 A CA 1170682A CA 000389369 A CA000389369 A CA 000389369A CA 389369 A CA389369 A CA 389369A CA 1170682 A CA1170682 A CA 1170682A
- Authority
- CA
- Canada
- Prior art keywords
- strip
- tip seal
- tip
- wrap element
- cross
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01C—ROTARY-PISTON OR OSCILLATING-PISTON MACHINES OR ENGINES
- F01C19/00—Sealing arrangements in rotary-piston machines or engines
- F01C19/08—Axially-movable sealings for working fluids
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
- F04C—ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; ROTARY-PISTON, OR OSCILLATING-PISTON, POSITIVE-DISPLACEMENT PUMPS
- F04C18/00—Rotary-piston pumps specially adapted for elastic fluids
- F04C18/02—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents
- F04C18/0207—Rotary-piston pumps specially adapted for elastic fluids of arcuate-engagement type, i.e. with circular translatory movement of co-operating members, each member having the same number of teeth or tooth-equivalents both members having co-operating elements in spiral form
- F04C18/0246—Details concerning the involute wraps or their base, e.g. geometry
- F04C18/0269—Details concerning the involute wraps
- F04C18/0284—Details of the wrap tips
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49229—Prime mover or fluid pump making
- Y10T29/49236—Fluid pump or compressor making
- Y10T29/4924—Scroll or peristaltic type
Abstract
ABSTRACT
A wrap element and tip seal are disclosed for use in fluid apparatus of the scroll type which include a wrap element having a groove disposed within its tip surface of spiroidal configuration generally conforming to that of the wrap element. A tip seal is disposed within the groove and comprises a relatively rigid strip of ma-terial having been wound about its longitudinal axis into a spiroidal configuration generally conforming to that of the groove, the strip of material having a cross section taken in a plane substantially perpendicular to its longi-tudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction. This configuration for the tip seal has the advantage that it may be formed using conventional winding techniques wherein a certain amount of "twist" about the longitudinal axis of the strip of material is normally encountered.
A wrap element and tip seal are disclosed for use in fluid apparatus of the scroll type which include a wrap element having a groove disposed within its tip surface of spiroidal configuration generally conforming to that of the wrap element. A tip seal is disposed within the groove and comprises a relatively rigid strip of ma-terial having been wound about its longitudinal axis into a spiroidal configuration generally conforming to that of the groove, the strip of material having a cross section taken in a plane substantially perpendicular to its longi-tudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction. This configuration for the tip seal has the advantage that it may be formed using conventional winding techniques wherein a certain amount of "twist" about the longitudinal axis of the strip of material is normally encountered.
Description
~...1'7(.~ 3Z
Description Title WRAP ELEMENT AND TIP SEAL
FOR USE IM FLUID APPA~ATUS
OF THE SCROLL TYPE AND
METHOD FOR ~ICING S~'~IE
Technical Field The present invention relates ~enerally to the field of fluid apparatus of the scroll type, including compressors, pumps, and expanders; and is specifically directed to an improvement in such apparatus relating to the tip seal provided therein which effects sealing between the axial tip portion of a wrap element and a cooperating end plate.
Background Art In the field of positive displacement fluid ap-paratus, there exists a class or category generally re-ferred to as scroll-type fluid apparatus which are characterized by the provision of wrap elements defining flank surfaces of generally spiroidal configuration about : respective axes, which wrap elements lie in intermeshing, angularly offset relationship with their axes generally parallel such that relative orbital motion between the : wrap elements results in the formation of one or more moving volumes between the wrap element9, defined by moving lines of coaction between the wraP elements at which th~r f~l~nk surfaces lie substantially tangent to each other. In a preferred form, the precise shape of the generally spiroidal flank surfaces com~rise an involute of a c rcle, however, the term "generally - spiroidal" is intended to encompass an~ form providing the requisite moving volumes during relative orbital motion between the wrap elements. Typically, end plate 1~'7(~6~Z
means are provided in sealing relationship to the wrap elements as they undergo xela.tive orbital motion such that the moving volumes are eff.ectively sealed. Reference may be had to U.S. Patent No. 801,182 for an early dis closure of scroll-type 1uid apparatus embodying this principle, or to U.S. Patent No. 3,~84,599 for a more recent disclosure.
It has been recognized that scroll-type fluid apparatus have.. utility in a wide variety of applications, including gas compressors or vacuum pumps for elevating the pressure of a gaseous working fluid; liquid pumps for trans-: porting a liquid working fluid; or as an expansion engine for producing mechanical work by the expansion of a rela-tively high pressure gaseous working fluid. In the case : 15 of a gas compressor, the moving volumes defined between wrap elements originate at a radially outer portion thereof and progress inwardly while their volume is reduced, re-sulting in compression of the working gas which is then discharged at a radially inner portion of the wrap ele-ments. Liquid pumps function in a similar fashion with the wrap elements configured such that no apprecia~le reduction ~- in volume occurs as the volumes progress radially inwardly, while scroll-type expansion engines receive a relatively : high~pressure gaseous woxking fluid at the radially inner portion of their wrap elements, which then progresses radially outwardly in the moving volumes as they increase in volume, resulting in expansion of the working fluid and production of mechanical work.
.
117(~6~3Z
In considering the kinematic relationship necessary in order to effect the requisite rel~tive or-bital motion between the wrap elements, it should be noted that at least three ~eneral approaches exist:
(1) maintainin~ one wrap element fixed while orbiting the other with respect thereto, i.e., causing it to under~o circular translation while main-taining a fixed angular relationship between the wrap elements;
Description Title WRAP ELEMENT AND TIP SEAL
FOR USE IM FLUID APPA~ATUS
OF THE SCROLL TYPE AND
METHOD FOR ~ICING S~'~IE
Technical Field The present invention relates ~enerally to the field of fluid apparatus of the scroll type, including compressors, pumps, and expanders; and is specifically directed to an improvement in such apparatus relating to the tip seal provided therein which effects sealing between the axial tip portion of a wrap element and a cooperating end plate.
Background Art In the field of positive displacement fluid ap-paratus, there exists a class or category generally re-ferred to as scroll-type fluid apparatus which are characterized by the provision of wrap elements defining flank surfaces of generally spiroidal configuration about : respective axes, which wrap elements lie in intermeshing, angularly offset relationship with their axes generally parallel such that relative orbital motion between the : wrap elements results in the formation of one or more moving volumes between the wrap element9, defined by moving lines of coaction between the wraP elements at which th~r f~l~nk surfaces lie substantially tangent to each other. In a preferred form, the precise shape of the generally spiroidal flank surfaces com~rise an involute of a c rcle, however, the term "generally - spiroidal" is intended to encompass an~ form providing the requisite moving volumes during relative orbital motion between the wrap elements. Typically, end plate 1~'7(~6~Z
means are provided in sealing relationship to the wrap elements as they undergo xela.tive orbital motion such that the moving volumes are eff.ectively sealed. Reference may be had to U.S. Patent No. 801,182 for an early dis closure of scroll-type 1uid apparatus embodying this principle, or to U.S. Patent No. 3,~84,599 for a more recent disclosure.
It has been recognized that scroll-type fluid apparatus have.. utility in a wide variety of applications, including gas compressors or vacuum pumps for elevating the pressure of a gaseous working fluid; liquid pumps for trans-: porting a liquid working fluid; or as an expansion engine for producing mechanical work by the expansion of a rela-tively high pressure gaseous working fluid. In the case : 15 of a gas compressor, the moving volumes defined between wrap elements originate at a radially outer portion thereof and progress inwardly while their volume is reduced, re-sulting in compression of the working gas which is then discharged at a radially inner portion of the wrap ele-ments. Liquid pumps function in a similar fashion with the wrap elements configured such that no apprecia~le reduction ~- in volume occurs as the volumes progress radially inwardly, while scroll-type expansion engines receive a relatively : high~pressure gaseous woxking fluid at the radially inner portion of their wrap elements, which then progresses radially outwardly in the moving volumes as they increase in volume, resulting in expansion of the working fluid and production of mechanical work.
.
117(~6~3Z
In considering the kinematic relationship necessary in order to effect the requisite rel~tive or-bital motion between the wrap elements, it should be noted that at least three ~eneral approaches exist:
(1) maintainin~ one wrap element fixed while orbiting the other with respect thereto, i.e., causing it to under~o circular translation while main-taining a fixed angular relationship between the wrap elements;
(2) orbiting both wrap elements in opposite directions while maintaining a fixed angular relationship therebetween; and
(3) rotating both wrap elements about offset, parallel axes while maintaining a fixed angular relationship therebetween.
A second consideration relevant to the relative orbital motion between wrap elements is the manner in which their flank surfaces are permitted to coact with each other; i.e., is actual contact permitted therebetween along the lines at which the surfaces lie substantially tangent, accompanied by a radial sealing force there-between; or are constraints imposed thereon so as to maintain a slight clearance or gap therebetween. In this regard, it is convenient to term the former as "radially compliant" type, while the latter may be re-ferred to as "fixed-crank" type. As used herein, the ~` term "moving line coaction" is intended to be descriptive of both types, while the term "actual moving line contact"
is limited to the radially compliant type. Reference may be had to U.S. Patent No. 3,924,977 for disclosure of a radially compliant type drive mechanism, while U.S.
~- ~ Patent No. 4,082,484 is illustrative of the fixed-crank type.
l t'7(~68Z
Reference may be had to the aforementioned U.S.
Patent No. 801,182 for an early disclosure of a tip seal for use in scroll appar~tus, while U.S. Patent No. 3,994,~36 is illustrative of a more recent development in this area.
In both these references, however, it is apparent that the seal elements disclosed therein areconstructed from strips of material having square or rectangular cross sections such that a relatively flat involute surface of the seal element is required to cooperate with a relatively flat surface of the groove formed in the wrap element. This requirement has been found to be a drawback in that very accurate machining or forming of the strip of material is re~uired in order to insure proper mating of the two sur-faces. Moreover, in the case where it is desired to form the tip seal from a strip of material using forming tech-niques such as winding, it has been found that the strip of material is susceptible to "twist" about its longitu-dinal axis during the winding process, resulting in a tip seal unsuitable for use without fùrther expensive machining operations of the involute surface or surfaces.
Disclosure of the Invention In accordance with the present invention, a wrap element and tip seal are provided wherein the wrap element defines first and second flank surface of generally spiroidal configuration about a reference axis, the flank surfaces extending generally in an axial direction and terminating in a tip surface lying in a plane substantially perpendicular to the axis. A groove is disposed within the tip surface also having a spiroidal configuration generally conforming to that of the flank surfaces, the groove including at least a radially outer lateral wall and a bottom wall. Disposed at least partially within the groove is a tip seal comprising a relatively rigid -l~,t~}~Z
strip of material having been wound about its longitudinal axis into spiroidal configuration generally conforming to that of the groove, the strip of material having a cross section taken in a plane substantially perpendicular to its longitudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction.
The groove itself mav include only a radially outer lateral wall and a bottom wall or, in the alternative, may include both radially inner and outer lateral walls as well as a bottom wall. Other variations in the con-figuration of the groove include the provision of a radially outer lateral wall which is inclined radially outwardly in ; a direction toward the tip surface.
The configuration of the aforementioned cross section of the strip of material comprising the seal ele-ment may be circular, so as to define a radially outer surface convex in a radially outward direction as well as a radially inner surface, convex in a radially inward direction. Alternatively, the cross section of the strip of material may include a generally flat sealing surface lying in a plane substantially perpendicular to the afore-mentioned reference axis and/or a generally flat base sur-face also lying in a plane substantially perpendicular to ~ the reference axis. In the preferred embodiment, the tip ; 25 seal is constructed from a strip of material comprising steel.
Further, in accordance with the invention, a variety of back-up means may be provided for imposing a force upon the strip of material in an axial direction away from the wrap element while permitting mavement thereof in an axial direction.
.
1~'7(~ 3Z
In accordance with another aspect of the inven-tion, a method of making the tip seal comprises winding a strip of relativel`y rigid material into generally spiroidal configuration about a reference axis, which strip of material has a cross section taken in a plane substantially perpendicular to its lon~itudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction.
Accordingly, it is a primary object of the present invention to provide a tip seal and method for making same wherein the tip seal comprises a strip of relatively rigid materiai having been wound into a gen-erally spiroidal configuration so as to cooperate with a groove formed in a wrap element, without the need for expensive machining of the radially outer and/or inner surfaces of the tip seal.
A further object of the invention is to provide a tip seal for use in fluid apparatus of the scroll type which can be formed from conventionally available material stocks, using known winding techniques, without resorting to expensive machining operations.
Yet another object of the invention is the pro-vision of a tip seal which effects a good secondary seal with a radially outer lateral wall of the groove, while also providing good axial sealing.
These and further objects of the invention will become apparent from a consideration of the detailed description of the invention which follows and by reference to the accompanying drawings.
;
11~7~6~3;Z
~rief Description of the Drawin~s Figure 1 is a plan view of a wrap element for use in fluid apparatus of the scroll type, including a tip seal constructed in accordance with the present invention.
Figure 2 is a cross section taken alon~ the line 2-2 of Figure 1.
Figure 3~a) is a cross section taken along the line 3-3 of Figure 1, illustrating a ~rior art tip seal.
Figure 3(b) through 3 (1) are cross section views taken along the line 3-3 of Figure 1, illustrating a variety of configurations which the tip seal and back-up means may take in accordance with the ~resent invention.
Figure 4 is a simplified schematic drawing il-lustrating generally winding apparatus of the type whichmay be used in fabricating a tip seal according to the method of the present invention.
Best Mode For Carrying Out The Invention Turning first to Figure 1 of the drawings, a wrap element for use in fluid apparatus of the scroll type is illustrated in plan view, designated generally by refer-ence numeral 1. Wrap element 1 includes a first, radially inner flank surface la and a second, radially outer flank surface lb which, as is apparent from Figure 1, are of generally spiroidal configuration about an axiæ or reference a~is 2. From Figure 2, it can be seen that the flank sur-faces la and lb extend in an axial direction and terminate in a tip surface 3 lying in a plane substantially perpen-dicular to axis 2.
~ S~8~
Disposed within tip surface 3 is a groove ha,ving a radiall~ outer lateral wall 4a, a radially inner lateral wall ~b, and a bottom wall 4c. As is apParent from Figure 1 the groove is of spiroidal configuration generally con-forming to that of flank surfaces la and lb, and has awidth measured in a generally radial direction with respect to axis 2 and a depth measured in an axial direction from tip surface 3.
Before proceeding to a detailed discussion of the novel tip seal comprising the present invention, it should be pointed out that wrap elements of th~ type il-lustrate~ in Figures 1 and 2 are well known to those skilled in the art of fluid apparatus of the scroll type, as dis- -cussed previousl~ in the subject application. As further illustrated in Figure 2, the wrap element may be affixed to an end plate 5 such that fluid apparatus of the scroll type may be constructed utilizing two, substantially iden-tical scroll members arranged in intermeshing, angularly offset relationship as described in many of the references alluded to previously.
Before proceeding to a discussion of the novel tip seal comprising the present invention, attention should be directed to Figure 3(a) of the drawings which comprises a cross section view of the prior art tip seal and illustrates a problem associated therewith which is solved by the present invention. As shown in Figure 3(a), it has been previously suggested in the field of scroll type fluid apparatus that a tip seal be provided therefor having a square or rectangular cross section and which , fits within the groove of the wrap element so as to pro-vide a close, sliding fit. While seals of this type have proven satisfactory in operation, they suffer fxom the drawback of being relatively expensive to manufacture in that the radially outer lateral wall 5a and radially inner lateral wall 5b must be machined to relatively close toler-:~1'7(~Z
ances in order to fit accurately within the groove machinedwithin the ti~ of the wrap element. While it would appear that the tip seal illustrated in Fi~ure 3(a) could be formed through a winding operation using a strip of mater-ial having the illustrated square or rectangular crosssection, this technique has proved to be unworkable due to "twist" along the longituainal axis of the strip of material as it undergoes the winding operation. This problem is illustrated in Figure 3(a) wherein the tip seal 5 is illustrated in a dotted line position brought about due to the aforementioned "twist" of the strip of material.
Obviously, such a tip seal would be unworkable without further machining operations due to the interference which would be presented with the lateral walls 4a and 4b of the groove.
Applicant has addressed the problem described immediately above and the solution thereto is illustrated in Figures 3(b) through 3(1) of the drawings. Turning first to Figure 3(b), it can be seen that applicant has provided a tip seal comprising a relatively rigid strip of material 6b which has been wound about its lon~itudinal axis into spiroidal configuration generally conforming to that of the groove. Specifically, strip 6b is shown to have a cross section taken in a plane substantially per-pendicular to its longitudinal axis wherein at least theradially outer surface 7a thereof is convex in a radially ; outward direction. More particularly, strip 6b is shown to have a substantially circular cross section as defined by a radially inner surface 7b convex in a radially in-ward direction, as well as a sealing surface 7c and base surface 7d of convex configuration.
Z
The use of a strip of material 6b having at least a radially outer surface which is convex in a ra-dially outward direction has a distinct advantage over the arrangement illustrated in Figure 3(a) since, even if strip 6b is twisted slightly about its longitudinal axis during the winding operation, surface 7a will simply be rotated slightly and continue to have a continuous line at which it remains tangent to radially outer lateral wall 4a. Thus, no relatively expensive machining operation is necessary in order to conform surface 7a to the involute configuration of surface 4a as would be required in the case illustrated in Figure 3(a).
As illustrated in Figure 3(b), tip seal 6b occupies a position within the groove such that surface 7a thereof is in actual sealing contact with lateral wall 4a. This is the position which the seal would occupy during operation of fluid apparatus of the scroll type wherein a higher fluid pressure exists adjacent the inner flank surface la than at radially outer flank surface lb;
the pressure differential urging tip seal 6b to the position indicated. It is thus apparent that a good secondary seal must be provided between surfaces 7a and 4a, which is accomplished by the present invention due to the convex configuration of surface 7a, providing good sealing con-tact irrespective of twist occurring in the tip seal during winding thereof. As will be appreciated by those skilled in the art, surface 7c of tip seal 6b provides axial sealing by contact with the end plate of a mating scroll member.
Continuing with reference to Figuxe 31b). it can be seen that tip seal 6b is urged in an axial direction by back-up means comprising a coil spring 9 having a cap mem-ber ll mounted on an en~ thereof. From Figure l, it can be seen that a plurality of coil springs 9 are provided, each disposed within a bore lO in the bottom wall of the li'7~ 68Z
groove, and spaced along the longitudi,nal axis of the tip seal at locations designed 9'. The back-up means serve not only to ur~e tip seal 6b into contact with the aforementioned mating scroll ~ember, but a,lso per-mit a certain degree of movement of the tip seal in anaxial direction so as to afford axial compliance within the fluid apparatus.
Turning next to Figure 3(c) of the drawings, a slight modification of that shown in Figure 3(b) is il-lustrated wherein the base surface 7d' of tip seal 6cis flattened in order to provide a broader seating sur-face for cap member 11. Surface 7d' may be formed prior to the winding of tip seal 6c, or afterward through a relatively simple qrindingoperation. In either event, it will be appreciated that the benefits associated with the convex configuration of surfaces 7a and 7b discussed previously will be realized.
Figure 3(d) of the drawings illustrates another modification in accordance with the present invention wherein tip seal 6d includes a flattened sealing surface 7c' for coaction with the flat end plate of the mating scroll member discussed above. Surface 7c' also may be formed either prior to the winding of tip seal 6d, or thereafter as by a grindingoperation. Once again the benefits of convex surfaces 7a and 7b are realized. The embodiment of Figure 3(d) differs further over that of Figures 3(b) and 3tc) in that no cap member 11 is provided between coil spring 9 and surface 7d of the tip seal.
Turning now to Figure 3(e), yet a further embodi-m nt of the invention is illustrated wherein tip seal 6a isprovi'ded with both a flattened base surface 7d' and a flat-tened sealing surface 7c~, as discussed previously. As be-fore, these flattened surfaces may be formed either prior to or after the seal element is wound into its spiroidal con-figuration. This embodiment is further distinguishedthrough the use of a coil spring 12 of the volute type as the back-up means.
11~7~ 2 Figure 3(f) of the drawings illustrates an em-bodiment wherein the tip seal 6f is substantially iden-tical to that illustrated in Figure 3(d), but wherein the back-up means employed differ substantially from those of the previous embodiments. Particularly, the back-up means illustrated in Figure 3(f) comprise an elongated spring member 14 disposed between bottom wall 4c of the groove and surface 7d of seal element 6f. Spring member 14 ex-tends along a longitudinal axis about the spiroidal con-figuration of groove 4 and has a position therein such that its radially outer edge portion 14a engages the bottom wall 4c of the groove while its radially inner edge portion 14b is axially spaced therefrom. With this configuration, spring member 14 acts according to the principle of the Belleville spring or washer such that an axial force is developed as edge portion 14b is displaced toward bottom wall 4c of the groove, thereby providing the axial force previously discussed while permitting limited axial movement of tip seal 6f. This type back-up member is described in our corresponding application Serial No. 389,379 filed November 4, 1981.
Figure 3(g) of the drawings illustrates a further embodiment of the invention, similar to that of Figure 3(f), with the exception that the back-up means comprise a length of resilient cord stock 13 disposed within the groove between its bottom wall 4c and the underside of tip seal 6g. This type back-up means is disclosed in previously referenced U.S. Patent No.3,994,636 and, as discussed therein, has the advantage of providing a positive secondary seal in order to prevent leakage underneath the seal element.
The embodiment of the invention illustrated in Figure 3(h), while incorporating a tip seal generally similar to that discussed with respect to Figure 3(e), differs in that the lateral walls of groove 4 are inclined as shown; radially outer lateral wall 4a' being inclined radially outwardly in a direction toward tip surface 3, and radially inner lateral wall 4b' bein~ inclined ra-dially inwardly in a direction towara tip surface 3.
This configuration has the advantage that, as tiP seal 6h is urged in a radially outward direction due to the pre-viously discussed pressure forces actin~ thereon, a com-ponent of the resultant force acting between surface 4a' and surface 7a urges tip seal 6h in an axial direction so as to increase the sealing force between it and the end plate of a cooperating scroll member.
Figure 3(i) illustrates an embodiment of the invention wherein the groove 4 is generally similar to that of Figure 3(h), but wherein no back-up means are employed for imposing an axial force upon tip seal 6i.
In this embodiment, only the pressure forces acting thereon are relied upon in order to urge the tip seal 6i into sealing engagement with radially outer lateral sur-face 4a' and with the end plate of a cooperating scroll member. Reference may be had to U.S. Patent No. 3,994,636 (Figure 3) for disclosure of a tip seal wherein no back-up means are employed.
Figure 3(j) of the drawings illustrates an em-bodiment wherein the groove disposed within wrap element 1 includes only a radially outer lateral wall 4a and a bottom wall 4c, an arran~ement disclosed in U.S. Patent No. 4,199,308. In this embodiment, tip seal 6j retains the configuration described with respect to the preceding embodiments wherein its radially outer surface 7a is con-vex in a radially outwara direction in order to achieve the previously discussed advantages associated therewith.This embodiment is similar to that of Figure 3(i) to the extent that no back-up means are provided and only the pressure forces acting on ti~ seal 6j are utilized in order to urge it into a sealing position.
6~Z
The embodiment of Figure 3(k) also includes a grooye having only a radially outer lateral wall 4a and a bottom wall 4c, and wherein tip seal 6k is generally similar to that illustrated with respect to Figures 3(d), (f), and (g). ~n this embodiment, back-up means in the form of an elongated spring member 14 as described with respect to Figure 4(f) are utilized.
Finally, the embodiment of Figure 3(1) incor-porates a groove having only a radially outer lateral wall 4a' and a bottom wall 4c, but wherein wall 4a' is inclined radially outwardly in a direction toward tip surface 3 as discussed with respect to Figure 3(h) and 3(i). As in the embodiment of Figure 3(k), an elongated spring member 14 is utilized as a back-up means.
lS It should now be apparent from the foregoing description of Figures 3(b) through 3(1) of the drawings that the present invention resides in the provision of a tip seal having a cross section taken in a plane substan-; tially perpendicular to its longitudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction, thereby avoiding the problem of twist during the winding thereof. As illustrated, the precise cross-section may take a number of forms, depending upon the configuration of the groove 4 into ` 25 which the tip seal must be inserted. For example, in the embodiments o Figures 3(b) through 3(g) wherein radially outer and inner lateral walls 4a and 4b are provided, it is preferable that both the radiall~ outer and inner surfaces 7a and 7b of the tip seal have the illustrated convex configuration. Moreover, depending upon the sealing chaxacteristics of the material of which the tip seal is constructed, and the particular back-up means utilized, it may be desirable to provide flattened sealing surfaces 7c' or flattened base surfaces 7d' on the tip seal.
6~f~
It is contemplated that the tip seal may be constructed from a variety of relatively rigid strips of material including not only metals such as steel or hard-ëned steel, but also plastic-type materials which are relatively rigid and capable of being wound into the requisite spiroidal configuration and maintaining that configuration after being wound.
Turning next to Figure 4 of the drawings, a simplified schematic diagram is provided to illustrate generally a method of making a tip seal in accordance with the present invention. Typically, the material of which the tip seal is constructed would be provided in strip form coiled on a spool or reel 8 mounted for rotation about a central axis. The strip of material 9 is lead therefrom through a set of rollers 10, following which it is engaged by a cam member 11 movable in the directions illustrated by the arrows thereby. As material 9 is en-gaged by cam member 11, it is bent in an upward direction (as viewed in Figure 4) so as to be wound into the required spiroidal configuration. As will be appreciated, cam member 11 is initially at a relatively high level with respect to strip of material 9 so as to wind the relatively small radius inner wraps of the tip seal, and it is grad-ually lowered during the winding operation so as to form the relatively larger radius outer wraps thereof. As pre-viously discussed, even though strip of material 9 may be subject to a degree of twist about its longitudinal axis during this operation, the resulting tip seal will nonetheless be suitable for use in the intended application as illustrated in Figure 3 of the drawings. As also pre-viously discussed, strip of ~aterial 9 may be of circular cross section initially, to be further machined subsequent to the winding operation; or may initially be formed to, say, the configuration of Figure 3(e) prior to the winding operation.
11'7(~682 While the invention has been described with respect to a number of specific embodiments, it is to be understood that variations thereto will become apparent to those skilled in the art upon a consideration thereof.
Accordingly, the scope of the invention is to be deter-mined in accordance with the scope and spirit of the claims which follow.
A second consideration relevant to the relative orbital motion between wrap elements is the manner in which their flank surfaces are permitted to coact with each other; i.e., is actual contact permitted therebetween along the lines at which the surfaces lie substantially tangent, accompanied by a radial sealing force there-between; or are constraints imposed thereon so as to maintain a slight clearance or gap therebetween. In this regard, it is convenient to term the former as "radially compliant" type, while the latter may be re-ferred to as "fixed-crank" type. As used herein, the ~` term "moving line coaction" is intended to be descriptive of both types, while the term "actual moving line contact"
is limited to the radially compliant type. Reference may be had to U.S. Patent No. 3,924,977 for disclosure of a radially compliant type drive mechanism, while U.S.
~- ~ Patent No. 4,082,484 is illustrative of the fixed-crank type.
l t'7(~68Z
Reference may be had to the aforementioned U.S.
Patent No. 801,182 for an early disclosure of a tip seal for use in scroll appar~tus, while U.S. Patent No. 3,994,~36 is illustrative of a more recent development in this area.
In both these references, however, it is apparent that the seal elements disclosed therein areconstructed from strips of material having square or rectangular cross sections such that a relatively flat involute surface of the seal element is required to cooperate with a relatively flat surface of the groove formed in the wrap element. This requirement has been found to be a drawback in that very accurate machining or forming of the strip of material is re~uired in order to insure proper mating of the two sur-faces. Moreover, in the case where it is desired to form the tip seal from a strip of material using forming tech-niques such as winding, it has been found that the strip of material is susceptible to "twist" about its longitu-dinal axis during the winding process, resulting in a tip seal unsuitable for use without fùrther expensive machining operations of the involute surface or surfaces.
Disclosure of the Invention In accordance with the present invention, a wrap element and tip seal are provided wherein the wrap element defines first and second flank surface of generally spiroidal configuration about a reference axis, the flank surfaces extending generally in an axial direction and terminating in a tip surface lying in a plane substantially perpendicular to the axis. A groove is disposed within the tip surface also having a spiroidal configuration generally conforming to that of the flank surfaces, the groove including at least a radially outer lateral wall and a bottom wall. Disposed at least partially within the groove is a tip seal comprising a relatively rigid -l~,t~}~Z
strip of material having been wound about its longitudinal axis into spiroidal configuration generally conforming to that of the groove, the strip of material having a cross section taken in a plane substantially perpendicular to its longitudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction.
The groove itself mav include only a radially outer lateral wall and a bottom wall or, in the alternative, may include both radially inner and outer lateral walls as well as a bottom wall. Other variations in the con-figuration of the groove include the provision of a radially outer lateral wall which is inclined radially outwardly in ; a direction toward the tip surface.
The configuration of the aforementioned cross section of the strip of material comprising the seal ele-ment may be circular, so as to define a radially outer surface convex in a radially outward direction as well as a radially inner surface, convex in a radially inward direction. Alternatively, the cross section of the strip of material may include a generally flat sealing surface lying in a plane substantially perpendicular to the afore-mentioned reference axis and/or a generally flat base sur-face also lying in a plane substantially perpendicular to ~ the reference axis. In the preferred embodiment, the tip ; 25 seal is constructed from a strip of material comprising steel.
Further, in accordance with the invention, a variety of back-up means may be provided for imposing a force upon the strip of material in an axial direction away from the wrap element while permitting mavement thereof in an axial direction.
.
1~'7(~ 3Z
In accordance with another aspect of the inven-tion, a method of making the tip seal comprises winding a strip of relativel`y rigid material into generally spiroidal configuration about a reference axis, which strip of material has a cross section taken in a plane substantially perpendicular to its lon~itudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction.
Accordingly, it is a primary object of the present invention to provide a tip seal and method for making same wherein the tip seal comprises a strip of relatively rigid materiai having been wound into a gen-erally spiroidal configuration so as to cooperate with a groove formed in a wrap element, without the need for expensive machining of the radially outer and/or inner surfaces of the tip seal.
A further object of the invention is to provide a tip seal for use in fluid apparatus of the scroll type which can be formed from conventionally available material stocks, using known winding techniques, without resorting to expensive machining operations.
Yet another object of the invention is the pro-vision of a tip seal which effects a good secondary seal with a radially outer lateral wall of the groove, while also providing good axial sealing.
These and further objects of the invention will become apparent from a consideration of the detailed description of the invention which follows and by reference to the accompanying drawings.
;
11~7~6~3;Z
~rief Description of the Drawin~s Figure 1 is a plan view of a wrap element for use in fluid apparatus of the scroll type, including a tip seal constructed in accordance with the present invention.
Figure 2 is a cross section taken alon~ the line 2-2 of Figure 1.
Figure 3~a) is a cross section taken along the line 3-3 of Figure 1, illustrating a ~rior art tip seal.
Figure 3(b) through 3 (1) are cross section views taken along the line 3-3 of Figure 1, illustrating a variety of configurations which the tip seal and back-up means may take in accordance with the ~resent invention.
Figure 4 is a simplified schematic drawing il-lustrating generally winding apparatus of the type whichmay be used in fabricating a tip seal according to the method of the present invention.
Best Mode For Carrying Out The Invention Turning first to Figure 1 of the drawings, a wrap element for use in fluid apparatus of the scroll type is illustrated in plan view, designated generally by refer-ence numeral 1. Wrap element 1 includes a first, radially inner flank surface la and a second, radially outer flank surface lb which, as is apparent from Figure 1, are of generally spiroidal configuration about an axiæ or reference a~is 2. From Figure 2, it can be seen that the flank sur-faces la and lb extend in an axial direction and terminate in a tip surface 3 lying in a plane substantially perpen-dicular to axis 2.
~ S~8~
Disposed within tip surface 3 is a groove ha,ving a radiall~ outer lateral wall 4a, a radially inner lateral wall ~b, and a bottom wall 4c. As is apParent from Figure 1 the groove is of spiroidal configuration generally con-forming to that of flank surfaces la and lb, and has awidth measured in a generally radial direction with respect to axis 2 and a depth measured in an axial direction from tip surface 3.
Before proceeding to a detailed discussion of the novel tip seal comprising the present invention, it should be pointed out that wrap elements of th~ type il-lustrate~ in Figures 1 and 2 are well known to those skilled in the art of fluid apparatus of the scroll type, as dis- -cussed previousl~ in the subject application. As further illustrated in Figure 2, the wrap element may be affixed to an end plate 5 such that fluid apparatus of the scroll type may be constructed utilizing two, substantially iden-tical scroll members arranged in intermeshing, angularly offset relationship as described in many of the references alluded to previously.
Before proceeding to a discussion of the novel tip seal comprising the present invention, attention should be directed to Figure 3(a) of the drawings which comprises a cross section view of the prior art tip seal and illustrates a problem associated therewith which is solved by the present invention. As shown in Figure 3(a), it has been previously suggested in the field of scroll type fluid apparatus that a tip seal be provided therefor having a square or rectangular cross section and which , fits within the groove of the wrap element so as to pro-vide a close, sliding fit. While seals of this type have proven satisfactory in operation, they suffer fxom the drawback of being relatively expensive to manufacture in that the radially outer lateral wall 5a and radially inner lateral wall 5b must be machined to relatively close toler-:~1'7(~Z
ances in order to fit accurately within the groove machinedwithin the ti~ of the wrap element. While it would appear that the tip seal illustrated in Fi~ure 3(a) could be formed through a winding operation using a strip of mater-ial having the illustrated square or rectangular crosssection, this technique has proved to be unworkable due to "twist" along the longituainal axis of the strip of material as it undergoes the winding operation. This problem is illustrated in Figure 3(a) wherein the tip seal 5 is illustrated in a dotted line position brought about due to the aforementioned "twist" of the strip of material.
Obviously, such a tip seal would be unworkable without further machining operations due to the interference which would be presented with the lateral walls 4a and 4b of the groove.
Applicant has addressed the problem described immediately above and the solution thereto is illustrated in Figures 3(b) through 3(1) of the drawings. Turning first to Figure 3(b), it can be seen that applicant has provided a tip seal comprising a relatively rigid strip of material 6b which has been wound about its lon~itudinal axis into spiroidal configuration generally conforming to that of the groove. Specifically, strip 6b is shown to have a cross section taken in a plane substantially per-pendicular to its longitudinal axis wherein at least theradially outer surface 7a thereof is convex in a radially ; outward direction. More particularly, strip 6b is shown to have a substantially circular cross section as defined by a radially inner surface 7b convex in a radially in-ward direction, as well as a sealing surface 7c and base surface 7d of convex configuration.
Z
The use of a strip of material 6b having at least a radially outer surface which is convex in a ra-dially outward direction has a distinct advantage over the arrangement illustrated in Figure 3(a) since, even if strip 6b is twisted slightly about its longitudinal axis during the winding operation, surface 7a will simply be rotated slightly and continue to have a continuous line at which it remains tangent to radially outer lateral wall 4a. Thus, no relatively expensive machining operation is necessary in order to conform surface 7a to the involute configuration of surface 4a as would be required in the case illustrated in Figure 3(a).
As illustrated in Figure 3(b), tip seal 6b occupies a position within the groove such that surface 7a thereof is in actual sealing contact with lateral wall 4a. This is the position which the seal would occupy during operation of fluid apparatus of the scroll type wherein a higher fluid pressure exists adjacent the inner flank surface la than at radially outer flank surface lb;
the pressure differential urging tip seal 6b to the position indicated. It is thus apparent that a good secondary seal must be provided between surfaces 7a and 4a, which is accomplished by the present invention due to the convex configuration of surface 7a, providing good sealing con-tact irrespective of twist occurring in the tip seal during winding thereof. As will be appreciated by those skilled in the art, surface 7c of tip seal 6b provides axial sealing by contact with the end plate of a mating scroll member.
Continuing with reference to Figuxe 31b). it can be seen that tip seal 6b is urged in an axial direction by back-up means comprising a coil spring 9 having a cap mem-ber ll mounted on an en~ thereof. From Figure l, it can be seen that a plurality of coil springs 9 are provided, each disposed within a bore lO in the bottom wall of the li'7~ 68Z
groove, and spaced along the longitudi,nal axis of the tip seal at locations designed 9'. The back-up means serve not only to ur~e tip seal 6b into contact with the aforementioned mating scroll ~ember, but a,lso per-mit a certain degree of movement of the tip seal in anaxial direction so as to afford axial compliance within the fluid apparatus.
Turning next to Figure 3(c) of the drawings, a slight modification of that shown in Figure 3(b) is il-lustrated wherein the base surface 7d' of tip seal 6cis flattened in order to provide a broader seating sur-face for cap member 11. Surface 7d' may be formed prior to the winding of tip seal 6c, or afterward through a relatively simple qrindingoperation. In either event, it will be appreciated that the benefits associated with the convex configuration of surfaces 7a and 7b discussed previously will be realized.
Figure 3(d) of the drawings illustrates another modification in accordance with the present invention wherein tip seal 6d includes a flattened sealing surface 7c' for coaction with the flat end plate of the mating scroll member discussed above. Surface 7c' also may be formed either prior to the winding of tip seal 6d, or thereafter as by a grindingoperation. Once again the benefits of convex surfaces 7a and 7b are realized. The embodiment of Figure 3(d) differs further over that of Figures 3(b) and 3tc) in that no cap member 11 is provided between coil spring 9 and surface 7d of the tip seal.
Turning now to Figure 3(e), yet a further embodi-m nt of the invention is illustrated wherein tip seal 6a isprovi'ded with both a flattened base surface 7d' and a flat-tened sealing surface 7c~, as discussed previously. As be-fore, these flattened surfaces may be formed either prior to or after the seal element is wound into its spiroidal con-figuration. This embodiment is further distinguishedthrough the use of a coil spring 12 of the volute type as the back-up means.
11~7~ 2 Figure 3(f) of the drawings illustrates an em-bodiment wherein the tip seal 6f is substantially iden-tical to that illustrated in Figure 3(d), but wherein the back-up means employed differ substantially from those of the previous embodiments. Particularly, the back-up means illustrated in Figure 3(f) comprise an elongated spring member 14 disposed between bottom wall 4c of the groove and surface 7d of seal element 6f. Spring member 14 ex-tends along a longitudinal axis about the spiroidal con-figuration of groove 4 and has a position therein such that its radially outer edge portion 14a engages the bottom wall 4c of the groove while its radially inner edge portion 14b is axially spaced therefrom. With this configuration, spring member 14 acts according to the principle of the Belleville spring or washer such that an axial force is developed as edge portion 14b is displaced toward bottom wall 4c of the groove, thereby providing the axial force previously discussed while permitting limited axial movement of tip seal 6f. This type back-up member is described in our corresponding application Serial No. 389,379 filed November 4, 1981.
Figure 3(g) of the drawings illustrates a further embodiment of the invention, similar to that of Figure 3(f), with the exception that the back-up means comprise a length of resilient cord stock 13 disposed within the groove between its bottom wall 4c and the underside of tip seal 6g. This type back-up means is disclosed in previously referenced U.S. Patent No.3,994,636 and, as discussed therein, has the advantage of providing a positive secondary seal in order to prevent leakage underneath the seal element.
The embodiment of the invention illustrated in Figure 3(h), while incorporating a tip seal generally similar to that discussed with respect to Figure 3(e), differs in that the lateral walls of groove 4 are inclined as shown; radially outer lateral wall 4a' being inclined radially outwardly in a direction toward tip surface 3, and radially inner lateral wall 4b' bein~ inclined ra-dially inwardly in a direction towara tip surface 3.
This configuration has the advantage that, as tiP seal 6h is urged in a radially outward direction due to the pre-viously discussed pressure forces actin~ thereon, a com-ponent of the resultant force acting between surface 4a' and surface 7a urges tip seal 6h in an axial direction so as to increase the sealing force between it and the end plate of a cooperating scroll member.
Figure 3(i) illustrates an embodiment of the invention wherein the groove 4 is generally similar to that of Figure 3(h), but wherein no back-up means are employed for imposing an axial force upon tip seal 6i.
In this embodiment, only the pressure forces acting thereon are relied upon in order to urge the tip seal 6i into sealing engagement with radially outer lateral sur-face 4a' and with the end plate of a cooperating scroll member. Reference may be had to U.S. Patent No. 3,994,636 (Figure 3) for disclosure of a tip seal wherein no back-up means are employed.
Figure 3(j) of the drawings illustrates an em-bodiment wherein the groove disposed within wrap element 1 includes only a radially outer lateral wall 4a and a bottom wall 4c, an arran~ement disclosed in U.S. Patent No. 4,199,308. In this embodiment, tip seal 6j retains the configuration described with respect to the preceding embodiments wherein its radially outer surface 7a is con-vex in a radially outwara direction in order to achieve the previously discussed advantages associated therewith.This embodiment is similar to that of Figure 3(i) to the extent that no back-up means are provided and only the pressure forces acting on ti~ seal 6j are utilized in order to urge it into a sealing position.
6~Z
The embodiment of Figure 3(k) also includes a grooye having only a radially outer lateral wall 4a and a bottom wall 4c, and wherein tip seal 6k is generally similar to that illustrated with respect to Figures 3(d), (f), and (g). ~n this embodiment, back-up means in the form of an elongated spring member 14 as described with respect to Figure 4(f) are utilized.
Finally, the embodiment of Figure 3(1) incor-porates a groove having only a radially outer lateral wall 4a' and a bottom wall 4c, but wherein wall 4a' is inclined radially outwardly in a direction toward tip surface 3 as discussed with respect to Figure 3(h) and 3(i). As in the embodiment of Figure 3(k), an elongated spring member 14 is utilized as a back-up means.
lS It should now be apparent from the foregoing description of Figures 3(b) through 3(1) of the drawings that the present invention resides in the provision of a tip seal having a cross section taken in a plane substan-; tially perpendicular to its longitudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction, thereby avoiding the problem of twist during the winding thereof. As illustrated, the precise cross-section may take a number of forms, depending upon the configuration of the groove 4 into ` 25 which the tip seal must be inserted. For example, in the embodiments o Figures 3(b) through 3(g) wherein radially outer and inner lateral walls 4a and 4b are provided, it is preferable that both the radiall~ outer and inner surfaces 7a and 7b of the tip seal have the illustrated convex configuration. Moreover, depending upon the sealing chaxacteristics of the material of which the tip seal is constructed, and the particular back-up means utilized, it may be desirable to provide flattened sealing surfaces 7c' or flattened base surfaces 7d' on the tip seal.
6~f~
It is contemplated that the tip seal may be constructed from a variety of relatively rigid strips of material including not only metals such as steel or hard-ëned steel, but also plastic-type materials which are relatively rigid and capable of being wound into the requisite spiroidal configuration and maintaining that configuration after being wound.
Turning next to Figure 4 of the drawings, a simplified schematic diagram is provided to illustrate generally a method of making a tip seal in accordance with the present invention. Typically, the material of which the tip seal is constructed would be provided in strip form coiled on a spool or reel 8 mounted for rotation about a central axis. The strip of material 9 is lead therefrom through a set of rollers 10, following which it is engaged by a cam member 11 movable in the directions illustrated by the arrows thereby. As material 9 is en-gaged by cam member 11, it is bent in an upward direction (as viewed in Figure 4) so as to be wound into the required spiroidal configuration. As will be appreciated, cam member 11 is initially at a relatively high level with respect to strip of material 9 so as to wind the relatively small radius inner wraps of the tip seal, and it is grad-ually lowered during the winding operation so as to form the relatively larger radius outer wraps thereof. As pre-viously discussed, even though strip of material 9 may be subject to a degree of twist about its longitudinal axis during this operation, the resulting tip seal will nonetheless be suitable for use in the intended application as illustrated in Figure 3 of the drawings. As also pre-viously discussed, strip of ~aterial 9 may be of circular cross section initially, to be further machined subsequent to the winding operation; or may initially be formed to, say, the configuration of Figure 3(e) prior to the winding operation.
11'7(~682 While the invention has been described with respect to a number of specific embodiments, it is to be understood that variations thereto will become apparent to those skilled in the art upon a consideration thereof.
Accordingly, the scope of the invention is to be deter-mined in accordance with the scope and spirit of the claims which follow.
Claims (22)
1. A wrap element and tip seal for use in fluid apparatus of the scroll type comprising a. a wrap element defining at least a first flank surface of generally spiroidal configuration about a reference axis, said flank surface extending generally in an axial direction and terminating in a tip surface lying in a plane substantially perpendicular to said reference axis;
b. a groove disposed within said tip sur-face of spiroidal configuration generally conforming to that of said flank surface, said groove including at least a radially outer lateral wall and having a width measured therefrom in a generally radial direction with respect to said axis and a depth measured in an axial direction from said tip surface; and c. a tip seal disposed at least partially within said groove and comprising a relatively rigid strip of material having been wound about its longitudinal axis into a spiroidal configuration generally conforming to that of said groove, said strip of material having a cross section taken in a plane substantially perpendicular to its longitudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction.
b. a groove disposed within said tip sur-face of spiroidal configuration generally conforming to that of said flank surface, said groove including at least a radially outer lateral wall and having a width measured therefrom in a generally radial direction with respect to said axis and a depth measured in an axial direction from said tip surface; and c. a tip seal disposed at least partially within said groove and comprising a relatively rigid strip of material having been wound about its longitudinal axis into a spiroidal configuration generally conforming to that of said groove, said strip of material having a cross section taken in a plane substantially perpendicular to its longitudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction.
2. The wrap element and tip seal of claim 1 wherein said wrap element defines first and second flank surfaces of generally spiroidal configuration, each which extends in an axial direction and terminates in said tip surface lying in a plane substantially perpen-dicular to said reference axis.
3. The wrap element and tip seal of claim 1 further comprising back-up means for imposing a force upon said strip of material in an axial direction away from said wrap element while permitting movement thereof in an axial direction.
4. The wrap element and tip seal of claim 1 wherein said strip of material comprises steel.
5. The wrap element and tip seal of claim 1 wherein said groove includes only a radially outer lateral wall and a bottom wall.
6. The wrap element and tip seal of claim 5 wherein the radially outer lateral wall of said groove is inclined radially outwardly in a direction toward said tip surface.
7. The wrap element and tip seal of claim 1 wherein said groove further includes a radially inner lateral wall, and wherein said cross section of said strip of material further includes a radially inner surface which is convex in a radially inward direction.
8. The wrap element and tip seal of claim 7 wherein the radially outer lateral wall of said groove is inclined radially outward toward said tip surface.
9. The wrap element and tip seal of claim 1, 2 or 3 wherein said cross section of said strip of material is substantially circular.
10. The wrap element and tip seal of claim 1, 2 or 3 wherein said cross section of said strip of material includes a generally flat sealing surface lying in a plane substantially perpendicular to said reference axis, said sealing surface lying proximate the tip surface of said wrap element.
11. The wrap element and tip seal of claim 1, 2 or 3 wherein said cross section of said strip of material includes a generally flat base surface lying in a plane substantially perpendicular to said reference axis, said base surface lying in a lower portion of said groove.
12. The wrap element and tip seal of claim 1, 2 or 3 wherein said cross section of said strip of material includes a generally flat sealing surface lying in a plane substantially perpendicular to said reference axis, and a generally flat base surface also lying in a plane substantially perpendicular to said reference axis; said sealing surface lying proximate the tip surface of said wrap element, and said base surface lying in a lower portion of said groove.
13. A tip seal for use in fluid apparatus of the scroll type comprising a relatively rigid strip of material having been wound about its longitudinal axis into a generally spiroidal configuration about a reference axis, said strip of material having a cross section taken in a plane substantially perpendicular to its longitudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction.
14. The tip seal of claim 13 wherein said cross section of said strip of material further includes a radially inner surface which is convex in a radially inward direction.
15. The wrap element and tip seal of claim 13 wherein said strip of material comprises steel.
16. The tip seal of claim 13 or 14 wherein said cross-section of said strip of material is substan-tially circular.
17. The tip seal of claims 13 or 14 wherein said cross section of said strip of material includes a generally flat sealing surface lying in a plane sub-stantially perpendicular to said reference axis.
18. The tip seal of claims 13 or 14 wherein said cross section of said strip of material includes a generally flat base surface lying in a plane substantially perpendicular to said reference axis.
19. The tip seal of claims 13 or 14 wherein said cross section of said strip of material includes a generally flat sealing surface lying in a plane substan-tially perpendicular to said reference axis, and a generally flat base surface also lying in a plane substantially per-pendicular to said reference axis.
20. A method of making a tip seal for use in fluid apparatus of the scroll type comprising winding a strip of relatively rigid material into generally spiroidal configuration about a reference axis, said strip of ma-terial having a cross section taken in a plane substantially perpendicular to its longitudinal axis wherein at least the radially outer surface thereof is convex in a radially outward direction.
21. The method of claim 20 wherein said strip of material comprises steel.
22. The method of claims 20 or 21 wherein said cross section of said strip of material is circular.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US232,527 | 1981-02-09 | ||
| US06/232,527 US4462771A (en) | 1981-02-09 | 1981-02-09 | Wrap element and tip seal for use in fluid apparatus of the scroll type and method for making same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1170682A true CA1170682A (en) | 1984-07-10 |
Family
ID=22873490
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000389369A Expired CA1170682A (en) | 1981-02-09 | 1981-11-04 | Wrap element and tip seal for use in fluid apparatus of the scroll type and method for making same |
Country Status (3)
| Country | Link |
|---|---|
| US (1) | US4462771A (en) |
| JP (1) | JPS57148003A (en) |
| CA (1) | CA1170682A (en) |
Families Citing this family (37)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6134379A (en) * | 1984-07-25 | 1986-02-18 | Sanden Corp | Scroll type compressor |
| US4627799A (en) * | 1984-08-27 | 1986-12-09 | Sanden Corporation | Axial sealing mechanism for a scroll type fluid displacement apparatus |
| JPS62126207A (en) * | 1985-11-27 | 1987-06-08 | Mitsubishi Electric Corp | Scroll hydraulic machine |
| US4811471A (en) * | 1987-11-27 | 1989-03-14 | Carrier Corporation | Method of assembling scroll compressors |
| US5226233A (en) * | 1992-01-31 | 1993-07-13 | General Motors Corporation | Method for inserting a tip seal in a scroll tip groove |
| JP3029228B2 (en) * | 1993-08-17 | 2000-04-04 | トーヨーエイテック株式会社 | Method and apparatus for processing scroll-shaped workpiece |
| JP3037557B2 (en) * | 1994-04-26 | 2000-04-24 | 株式会社デンソー | Scroll member molding method |
| JP3369786B2 (en) * | 1995-04-19 | 2003-01-20 | サンデン株式会社 | Scroll compressor |
| US6511308B2 (en) | 1998-09-28 | 2003-01-28 | Air Squared, Inc. | Scroll vacuum pump with improved performance |
| US6129530A (en) * | 1998-09-28 | 2000-10-10 | Air Squared, Inc. | Scroll compressor with a two-piece idler shaft and two piece scroll plates |
| US6074185A (en) * | 1998-11-27 | 2000-06-13 | General Motors Corporation | Scroll compressor with improved tip seal |
| CA2325752A1 (en) * | 2000-06-01 | 2001-12-01 | Michael V. Kazakis | Oiless rotary scroll air compressor tipseal assembly |
| US6585501B2 (en) * | 2000-11-06 | 2003-07-01 | Mitsubishi Heavy Industries, Ltd. | Scroll compressor sealing |
| US8523544B2 (en) | 2010-04-16 | 2013-09-03 | Air Squared, Inc. | Three stage scroll vacuum pump |
| US7942655B2 (en) * | 2006-02-14 | 2011-05-17 | Air Squared, Inc. | Advanced scroll compressor, vacuum pump, and expander |
| US10683865B2 (en) | 2006-02-14 | 2020-06-16 | Air Squared, Inc. | Scroll type device incorporating spinning or co-rotating scrolls |
| US10221852B2 (en) | 2006-02-14 | 2019-03-05 | Air Squared, Inc. | Multi stage scroll vacuum pumps and related scroll devices |
| US8668479B2 (en) * | 2010-01-16 | 2014-03-11 | Air Squad, Inc. | Semi-hermetic scroll compressors, vacuum pumps, and expanders |
| US7547202B2 (en) | 2006-12-08 | 2009-06-16 | Emerson Climate Technologies, Inc. | Scroll compressor with capacity modulation |
| US8333143B2 (en) * | 2009-07-31 | 2012-12-18 | Yu-Hui Liao | Hydraulic cylinder device |
| GB2472637B (en) | 2009-08-14 | 2015-11-25 | Edwards Ltd | Scroll Compressor With Plural Sealing Types |
| GB0914230D0 (en) * | 2009-08-14 | 2009-09-30 | Edwards Ltd | Scroll pump |
| US11047389B2 (en) | 2010-04-16 | 2021-06-29 | Air Squared, Inc. | Multi-stage scroll vacuum pumps and related scroll devices |
| US20130232975A1 (en) | 2011-08-09 | 2013-09-12 | Robert W. Saffer | Compact energy cycle construction utilizing some combination of a scroll type expander, pump, and compressor for operating according to a rankine, an organic rankine, heat pump, or combined organic rankine and heat pump cycle |
| EP3163129B1 (en) * | 2014-06-27 | 2020-10-14 | Kabushiki Kaisha Riken | Piston ring |
| US10508543B2 (en) | 2015-05-07 | 2019-12-17 | Air Squared, Inc. | Scroll device having a pressure plate |
| US10865793B2 (en) | 2016-12-06 | 2020-12-15 | Air Squared, Inc. | Scroll type device having liquid cooling through idler shafts |
| WO2019212598A1 (en) | 2018-05-04 | 2019-11-07 | Air Squared, Inc. | Liquid cooling of fixed and orbiting scroll compressor, expander or vacuum pump |
| US11067080B2 (en) | 2018-07-17 | 2021-07-20 | Air Squared, Inc. | Low cost scroll compressor or vacuum pump |
| US20200025199A1 (en) | 2018-07-17 | 2020-01-23 | Air Squared, Inc. | Dual drive co-rotating spinning scroll compressor or expander |
| US11530703B2 (en) | 2018-07-18 | 2022-12-20 | Air Squared, Inc. | Orbiting scroll device lubrication |
| CN109185144B (en) * | 2018-11-01 | 2020-11-13 | 珠海格力电器股份有限公司 | Sealing structure and vortex type air compressor with same |
| US11473572B2 (en) | 2019-06-25 | 2022-10-18 | Air Squared, Inc. | Aftercooler for cooling compressed working fluid |
| WO2021144846A1 (en) * | 2020-01-14 | 2021-07-22 | 三菱電機株式会社 | Scroll compressor and refrigeration cycle device |
| US11898557B2 (en) | 2020-11-30 | 2024-02-13 | Air Squared, Inc. | Liquid cooling of a scroll type compressor with liquid supply through the crankshaft |
| US11885328B2 (en) | 2021-07-19 | 2024-01-30 | Air Squared, Inc. | Scroll device with an integrated cooling loop |
| EP4174285A1 (en) * | 2022-12-22 | 2023-05-03 | Pfeiffer Vacuum Technology AG | Scroll vacuum pump |
Family Cites Families (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US56699A (en) * | 1866-07-31 | Improvement in piston-packings | ||
| US1965294A (en) * | 1925-10-16 | 1934-07-03 | Lewis C Marshall | Piston ring |
| US2259422A (en) * | 1939-12-07 | 1941-10-14 | Chicago Seal Company | Shaft seal |
| US3059584A (en) * | 1960-01-13 | 1962-10-23 | Sonic Eng Corp | Rotary pumps and compressors |
| US3235273A (en) * | 1962-08-23 | 1966-02-15 | Goodrich Co B F | Relatively rotatable seal assembly having eccentric sealing contact |
| US3476397A (en) * | 1966-02-04 | 1969-11-04 | Alfa Laval Ab | Seal between stationary and rotary parts |
| US3994636A (en) * | 1975-03-24 | 1976-11-30 | Arthur D. Little, Inc. | Axial compliance means with radial sealing for scroll-type apparatus |
| US4176848A (en) * | 1978-06-30 | 1979-12-04 | Dresser Industries, Inc. | Rotary bearing seal for drill bits |
| US4199308A (en) * | 1978-10-02 | 1980-04-22 | Arthur D. Little, Inc. | Axial compliance/sealing means for improved radial sealing for scroll apparatus and scroll apparatus incorporating the same |
| US4290497A (en) * | 1979-07-24 | 1981-09-22 | Eduardo Barnetche | Automatic wear compensating seal device |
-
1981
- 1981-02-09 US US06/232,527 patent/US4462771A/en not_active Expired - Lifetime
- 1981-11-04 CA CA000389369A patent/CA1170682A/en not_active Expired
-
1982
- 1982-02-04 JP JP57015612A patent/JPS57148003A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| US4462771A (en) | 1984-07-31 |
| JPS6354881B2 (en) | 1988-10-31 |
| JPS57148003A (en) | 1982-09-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1170682A (en) | Wrap element and tip seal for use in fluid apparatus of the scroll type and method for making same | |
| US4415317A (en) | Wrap element and tip seal for use in fluid apparatus of the scroll type | |
| US5836752A (en) | Scroll-type compressor with spirals of varying pitch | |
| US3994635A (en) | Scroll member and scroll-type apparatus incorporating the same | |
| CA1133958A (en) | Axial compliance/sealing means for improved radial sealing for scroll apparatus and scroll apparatus incorporating the same | |
| US5035589A (en) | Method and apparatus for reducing scroll compressor tip leakage | |
| AU672560B1 (en) | Scroll type fluid machine | |
| JPH0440521B2 (en) | ||
| JPS59131702A (en) | Scroll type machine and its manufacture | |
| CA1222987A (en) | Scroll type fluid displacement apparatus | |
| JPH07324689A (en) | Scroll type fluid compressor | |
| KR970001456B1 (en) | Scroll machine | |
| US5056336A (en) | Scroll apparatus with modified scroll profile | |
| GB2220708A (en) | Scroll compression apparatus | |
| CN100402855C (en) | Scroll compressor | |
| US5520527A (en) | Apparatus for adjusting orbital radius in a scroll compressor | |
| JP2834888B2 (en) | Scroll compressor | |
| JPH0135196B2 (en) | ||
| JP3590432B2 (en) | Scroll machine | |
| JP3201901B2 (en) | Scroll type compressor | |
| AU768287B2 (en) | Conjugate screw rotor profile | |
| JP3445794B2 (en) | Scroll type fluid discharge device with high specific volume ratio and semi-compliant bias mechanism | |
| KR100296696B1 (en) | Volumetric fluid compressor and film formation method | |
| US6071101A (en) | Scroll-type fluid displacement device having flow diverter, multiple tip seal and semi-radial compliant mechanism | |
| JPH0127273B2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |